FIG. 21 illustrates a conventional detection system disclosed in Patent Literature 1, among various detection systems proposed in the past.
This detection system is intended for an automobile and includes: a light-emitting diode (LED) lamp 12 provided at the front part of the automobile as an infrared light source; a camera 13 as an imaging unit; a control circuit 14 provided inside the automobile as a control unit; and a monitor 15 as a display unit.
The LED lamp 12 is a light source different from a headlight light source provided for lighting up a dark place. The LED lamp 12 is provided in the vicinity of an edge of an automobile's bumper and emits near-infrared light having a wavelength of 880 nm, for example.
To implement an active system, the camera 13 includes a solid-state imaging sensor sensitive to the near-infrared light emitted by the LED lamp 12, and captures images using the near-infrared light.
As the monitor 15, a specialized monitor provided in the automobile's interior is used, or a monitor for a car navigation system, for example, is used, and the screen of the monitor shows the captured images mentioned above. Or, the monitor 15 is provided as a head-up display that shows the captured images on a screen provided on the inner surface of the windshield.
To implement a passive system, infrared receiving devices 16 detect infrared light emitted from pedestrians, animals, etc.